I was at school today, and I decided that I would skate down one of the railings outside my school on my rollerblades(I do it all the time), and some asshole decided to park their moped near the boottom of the rail. Needless to say, I got my arm jammed between the bike tire and the railing.
It can actually be easier to play with one arm. ...You just can't strum. XD This is where an electric guitar and crap loads of gain come in handy.